1. Field of the Invention
The present invention relates to an image forming apparatus, such as a facsimile machine, a printer, a copying machine, or other similar image forming apparatus, and more particularly to a process cartridge detachably attached to a main body of an image forming apparatus.
2. Discussion of the Related Art
An image forming apparatus including a cleaning device that removes residual toner attached onto a surface of a photoconductive drum has been widely used. The photoconductive drum functions as one of the moving members used in the image forming apparatus, and will be referred to as a moving member hereafter. In such an image forming apparatus, a lubricant is applied onto a surface of the moving member to decrease the coefficient of friction between the surface of the moving member and a cleaning blade of the cleaning device that contacts the surface of the moving member. By doing so, the wear of the surface of the moving member by the cleaning blade and the abrasion of the cleaning blade are avoided. As a result, the useful lifetime of the moving member may be extended, and image deterioration caused by poor cleaning performance of the cleaning blade may be minimized or avoided. The above-described image forming apparatus is described, for example, in Published Japanese patent application Nos. 2000-35727, 2000-231299, and 2001-51561.
There is a background image forming apparatus (hereafter referred to as a “first background image forming apparatus”) in which a lubricant is applied onto a surface of a moving member, such as a photoconductive drum, and an intermediate transfer element, by bringing a solid lubricant into contact with the surface of the moving member. There is another background image forming apparatus (hereafter referred to as a “second background image forming apparatus”) in which a solid lubricant is scrapped off by a brush roller and is transformed into a powder lubricant. The powder lubricant is applied to a surface of a moving member, such as a photoconductive drum, and an intermediate transfer element, by the brush roller. In these first and second background image forming apparatuses, if the solid lubricant and the brush roller are not accommodated in a casing, a part of the lubricant to be applied onto the surface of the moving member is typically scattered in the image forming apparatus. Because the lubricant is wasted due to the scattered lubricant, a greater amount of lubricant than necessary needs to be prepared considering the waste of lubricant. In this case, the greater amount of lubricant may hinder the downsizing of the image forming apparatus.
Further, there is another background image forming apparatus (hereafter referred to as a “third background image forming apparatus”) in which a lubricant applying mechanism is provided in a cleaning device. For example, in the lubricant applying mechanism, a solid lubricant is scraped off by a brush roller, and the scraped lubricant is applied onto a surface of a moving member. Generally, a cleaning device is configured to collect toner removed from a surface of a moving member by a cleaning member, and the collected toner does not scatter from the cleaning device into a main body of an image forming apparatus. Therefore, the solid lubricant scraped off by the brush roller in the cleaning device does not scatter from the cleaning device into a main body of an image forming apparatus.
However, in the third background image forming apparatus, when the rotating brush roller scrapes off the solid lubricant and applies the scraped lubricant onto the surface of the moving member, a part of the scraped lubricant scatters in the cleaning device. The lubricant scattered in the cleaning device is conveyed together with toner removed from the surface of the moving member by the cleaning member to a container, such as a waste toner collection bottle. Similar to the first and second background image forming apparatuses, a greater amount of lubricant than necessary needs to be prepared considering the waste of lubricant (i.e., the scattered lubricant) in the third background image forming apparatus. In this case, a greater amount of lubricant may prevent the downsizing of the image forming apparatus.
The above-described problem of wasting lubricants occurs not only in the above-described configurations, but also occurs in a configuration in which an originally powdered lubricant (i.e., not a lubricant transformed from a solid lubricant to a powder lubricant) is applied onto a surface of a moving member, and in a configuration in which a liquid lubricant is applied to a surface of a moving member, and in other configurations.